// Copyright 2020 Google Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//      http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

#include <cstddef>

#include <cstdint>

#include <opencv2/opencv.hpp>

#include <fuzzer/FuzzedDataProvider.h>

namespace {

bool GetCVImage(const std::string& image_string, const int max_pixels,

                cv::Mat* original_image) {

  if (image_string.empty()) return false;

  std::vector<uchar> raw_data(image_string.size());

  const char* ptr = image_string.data();

  std::copy(ptr, ptr + image_string.size(), raw_data.data());

  try {

    *original_image = cv::imdecode(raw_data, cv::IMREAD_UNCHANGED);

  } catch (cv::Exception e) {}

  return !original_image->empty();

}

void TestExternalMethods(const cv::Mat& mat) {

  try{

    cv::sum(mat);

  } catch (cv::Exception e) {}

  try {

    cv::mean(mat);

  } catch (cv::Exception e) {}

  try {

    cv::trace(mat);

  } catch (cv::Exception e) {}

}

void TestInternalMethods(const cv::Mat& mat) {

  try {

    mat.t();

  } catch (cv::Exception e) {}

  try {

    mat.inv();

  } catch (cv::Exception e) {}

  try {

    mat.diag();

  } catch (cv::Exception e) {}

}

void TestSplitAndMerge(const cv::Mat& image) {

  std::vector<cv::Mat> split_image(image.channels());

  cv::split(image, split_image);

  if (!split_image.empty()) {

    cv::Mat new_image;

    cv::merge(split_image, new_image);

  }

}

}  // namespace

extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {

  // Prepares a backup image we will use if we cannot successfully get an image

  // by decoding the string.

  std::vector<uint8_t> image_data = {data, data + size};

  cv::Mat backup_image =

      cv::Mat(1, image_data.size(), CV_8UC1, image_data.data());

  FuzzedDataProvider fuzzed_data_provider(data, size);

  const int max_pixels = fuzzed_data_provider.ConsumeIntegral<int>();

  const std::string image_string =

      fuzzed_data_provider.ConsumeRemainingBytesAsString();

  cv::Mat original_image;

  // Tests the clone method.

  cv::Mat cloned_image = GetCVImage(image_string, max_pixels, &original_image)

                             ? original_image.clone()

                             : backup_image.clone();

  // TODO: enabling the following crashes right away.

  // TestExternalMethods(cloned_image);

  TestInternalMethods(cloned_image);

  TestSplitAndMerge(cloned_image);

  return 0;

}